Objective To explore the feasibility and accuracy of dual-source CT (DSCT)in evaluating aortic regurgitation (AR). Methods Among 78 patients who underwent both DSCT and TTE,38 patients were diagnosed as AR and 40 without AR served as controls.Maximum regurgitant orifice area (ROA)in diastole was planimetrically measured with DSCT,and measurements were compared with semiquantitative classification of TTE.Results DSCT correctly identified 37 patients with AR.Compared with TTE,two patients were false positive and three patients were false negative findings by DSCT (sensitivity 92%,specificity 95%, positive predictive value 94%,and negative predictive value 93%).ROA measured by DSCT (0.32 cm2 ±0.44 cm2 )was signifi-cantly correlated with TTE classification (r=0.85,P<0.01).With receiver operating characteristic curve analysis,discrimination between degrees of AR with DSCT was high accurate when using cutoff ROAs of 0.08 cm2 and 0.58 cm2 .Conclusion Planimetric measurement of ROA with DSCT is accurate for the quantitative evaluation of AR.

Objective To discuss the feasibility and accuracy of dual-source CT ( DSCT) in the evaluation of aortic stenosis ( AS) with transthoracic echocardiography ( TTE) as reference.Methods A total of 53 patients who underwent both DSCT and TTE were prospectively evaluated.All of them were assessed by TTE for aortic stenosis.Maximum aortic valve area ( AVA) in systolic phase was measured with DSCT , and was compared to that index obtained from the continuity equation on TTE.The severity of AS was graded as mild , moderate , or severe according to the AVA.Linear regression analysis and Bland-Altman plots were used to compare the AVA measured by using CT and TTE.Agreement on semi-quantitative grades of AS severity between the two methods was tested by using Kappa statistics.Results The mean AVA using DSCT was (1.45 ±0.35 ) cm2 compared to the mean AVA of ( 1.33 ±0.36 ) cm2 using TTE, with a significant correlation between them (r=0.92,P<0.01).Bland-Altman analysis demonstrated good inter-modality consistency between DSCT and TTE.However , DSCT demonstrated a slight overestimation of the AVA compared to TTE.As identified by TTE, there were 53 patients with AS, 13 with mild AS, 21 with moderate AS , and 19 with severe AS.In 3 patients DSCT showed no AS , TTE detected mild AS.In 6 cases, TTE had graded the stenosis as moderate , but the stenosis degree was graded as mild using DSCT.Kappa analysis showed a good agreement between the two methods on semi -quantitative grades of aortic stenosis severity (Kappa=0.75,P<0.01).Conclusion AVA measurements using DSCT is feasible and reasonably accurate for those patients with moderate to severe aortic stenosis.

Objective To explore the feasibility and accuracy of dual-source computed tomography(DSCT)coronary angiography for evaluation the morphology and motion of aortic valve.Methods A total of 125 cases with suspected coronary artery disease un-derwent computed tomography coronary angiography and transthoracic echocardiography examination.Twenty CT data sets were re-constructed in 5% steps from 0% to 95% of R-R interval.The morphologic features,changes of motion and image quality of the aortic valve in cardiac cycle were observed and recorded with CT dynamic cine-mode technique.The differences of aortic opening area in the various phases of the systole were analyzed by using ANOVA.Results 92.3% of aortic valve images among the total 2500 phases were good enough for evaluated in the 125 patients examined.DSCT visualized 123 patients with tricuspid aortic valve while 2 patients with bicuspid aortic valve.27 patients with degenerative aortic valve disease were identified.CT correctly identified 26 patients with aor-tic insufficiency during diastole.Compared with TTE,3 patients were false positives and two patients were false negatives on DSCT. Aortic valve opening was seen in phase 0% to 35% in 92% of patients,and it was closed during phase 40% to 95% of R-R interval in 75.2% of patients.There were significant difference between the AVA in the various phases of the systole(F =2.97,P <0.05). Conclusion DSCT allows accurate and dynamic visualization of morphology and motion of aortic valve throughout the cardiac cycle. The area of the aortic opening is widest and image quality is best during midsystole.